This is the ideal word for an Italian to express his nonchalant attitude towards a particular subject.
The word "mah" may also be used instead of "bah".
Me, all I knows is, I saw your girl wit Gino doin' stuff that me I wouldn't do wit your girl.
Bah, who cares...I gave her herpes...we're freakin'even you know...
The word "bah" differs from other popular internet shorthand such as "lol" because it is not an accronym, but rather a word that sounds like it is spelled.
Gearoid: "Flying through the Pokémon episodes bah." ( Gearoid informs his friend that he is watching Pokémon episodes and is possibly bored out of his proverbial tree.)
Shane: "Fair love me friends bah." ( Here, Shane uses the word to emphasize how much he loves his friends. )
Philip: "Well bah." ( A common greeting between the exponents of bah. Conversations like this are notorious for their length and content. )